Magnetically anchored, quick release pin

ABSTRACT

A magnetically anchored quick release pin is provided for quickly and accurately preventing movement between two objects and/or quickly changing the relative position between two objects. One such use is in a weight lifting machine providing for variable resistance, which can be adjusted manually during a workout routine. The weight lifting machine includes one or more guides and a stack of weights which are slidably mounted on the guides and movable along the guides from a rest position to an elevated position. The weight lifting machine also includes a selector member and a lift member. Each of the weights includes an opening to receive a selector pin. The openings are aligned to define a passage through the stack of weights to allow the selector pin to couple each of the weights in the stack to the selector member. The selector pin has a magnetic means affixed thereto to enable one to couple and decouple from respective weights of the stack of weights without having to release a locking mechanism on the selector pin. The lift member is adapted to permit a user of the weight lifting machine to, for example, pull and thereby raise the weights coupled to the selector member from their respective rest positions to their respective elevated positions.

CROSS-REFERENCE TO RELATED APPLICATION

[0001] The present application claims priority to provisional application Serial No. 60/316,778, filed Aug. 31, 2001, which is relied on and incorporated herein by reference.

FIELD OF THE INVENTION

[0002] The present invention relates to use of a magnetically anchored pin anywhere a releasable or a quick release pin is presently used, including, but not limited to, exercise equipment and more particularly, to the selection of a desired number of aligned weights for resistance to exercise movement.

BACKGROUND OF THE INVENTION

[0003] Releasable or quick release pins have many uses for maintaining relative positions of various articles, preventing movement of various articles relative to each other and the like. One such well-known use of quick release pins is in exercise equipment. Exercise weight stacks are well known in the art and prevalent in the exercise equipment industry. Generally speaking, a plurality of weights or plates are arranged in a stack and maintained in alignment by rods or other guide members. A desired amount of weight is engaged by selectively connecting a selector rod to the appropriate weight in the stack. The selector rod and/or the uppermost weight in the stack are/is connected to at least one force receiving member by means of a connector. The engaged weight is lifted up from the stack in response to movement of the force receiving member.

[0004] Some examples of conventional weight stacks, their applications, and/or features are disclosed in U.S. Pat. No. 3,912,261 to Lambert, Sr. (shows an exercise machine which provides weight stack resistance to a single exercise motion); U.S. Pat. No. 5,263,915 to Habing (shows an exercise machine which uses a single weight stack to provide resistance to several different exercise motions); U.S. Pat. No. 4,900,018 to Ish III, et al. (shows an exercise machine which provides weight stack resistance to a variety of exercise motions); U.S. Pat. No. 4,878,663 to Luquette (shows an exercise machine which has rigid linkage members interconnected between a weight stack and a force receiving member); U.S. Pat. No. 4,601,466 to Lais (shows bushings which are attached to weight stack plates to facilitate movement along conventional guide rods); U.S. Pat. No. 5,374,229 to Sencil (shows an alternative to conventional guide rods); U.S. Pat. No. 4,878,662 to Chem (shows a selector rod arrangement for clamping the selected weights together into a collective mass); U.S. Pat. No. 4,809,973 to Johns (shows telescoping safety shields which allow insertion of a selector pin but otherwise enclose the weight stack); U.S. Pat. No. 5,000,446 to Samo (shows discrete selector pin configurations intended for use on discrete machines); U.S. Pat. No. 4,546,971 to Raasoch (shows levers operable to remotely select a desired number of weights in a stack); U.S. Pat. No. 5,037,089 to Spagnuolo et al. (shows a controller operable to automatically adjust weight stack resistance); U.S. Pat. No. 4,411,424 to Barnett (shows a dual-pronged pin which engages opposite sides of a selector rod); U.S. Pat. No. 1,053,109 to Reach (shows a stack of weight plates, each having a slide which moves into and out of engagement with the weight plate or top plate above it); and U.S. Pat. No. 5,306,221 to Itaru (shows a stack of weight plates, each having a lever which pivots into and out of engagement with a selector rod. Despite these advances and others in the weight stack lifting equipment industry, room for improvement and ongoing innovation continues to exist.

[0005] More recently, exercise devices have incorporated variable resistance capabilities which allow the user of the exercise machine to maximize his or her benefits from the machine. For example, in U.S. Pat. No. 5,037,089 to Spagnuolo weights are selected by mechanical actuators which are controlled by the user of the exercise machine. The mechanical actuator includes a solenoid and a pin, which is held in place by a spring. When the solenoid is energized, the pin is withdrawn from the weight which reduces the resistance for the user of apparatus. The solenoids are controlled by a module which includes a microprocessor which permits the user of the equipment to increase or decrease the weight as desired. The decoupling and coupling is not instantaneous and there may be increased potential for jams, which result from misalignment of the pins with the select bar. Because these type of jams can not be manually fixed, there is a great potential for interruption.

SUMMARY OF THE INVENTION

[0006] One aspect of the present invention is to provide a selector pin having a magnetic engagement means for affixing to aligned weight plates. The magnetic engagement means may be affixed to the selector pin along the longitudinal axis of the selector pin. Additional features and advantages of the present invention will become apparent to those skilled in the art from the more detailed description that follows.

[0007] The present invention relates to the use of a magnetically anchored releasable pin to prevent or lessen relative movement between two articles and is applicable anywhere a releasable pin or a quick release pin is presently used. One such use is in a weight lifting machine and, more particularly, to a weight lifting machine which permits the user to select a sequence in which the weight is increase or decreased at various intervals during the workout routine or permits the user to adjust the weight during the workout routine. Conventional weight lifting machines comprise a frame which includes a pair of spaced apart generally vertical tracks with a plurality of weights and a carriage movably mounted on the tracks. The carriage typically includes a selection rod, post or bar which extends through the central portions of the weights and is manually coupled to one or more of the weights to increase or decrease the weight coupled to the carriage. Typically, the weights are coupled to the selection rod by a removable pin which extends through the weight and through a corresponding aperture in the selection rod. The carriage also is connected to a cable on the distal end of which is connect a handle bar, with the cable being supported on the frame by a pair of pulleys. Therefore, when the user of the machine pulls on the handle bar the carriage moves up the tracks, with the resistance being a function of the number of weights that are coupled to the carriage. In order to vary the weight on the carriage, and therefore the resistance for the user of the machine, the user of the machine must return the carriage to the starting position and relocate the pin either to reduce the number of weights attached to the selection rod or increase the number of weights attached to the select bar.

[0008] Accordingly the present invention provides a weight lifting machine which includes at least one guide and a stack of weights which are slidably mounted on the guide and movable along the guide from a rest position to an elevated position. The weightlifting machine also includes a selector rod, a lift cable, and optionally a lift bar. Each of the weights includes an opening therein or between the adjacent weight to receive a selector pin. The openings are aligned to define a passage through the stack of weights to allow the selector pin to contact each of the weights in the stack. The selector pin includes a magnetic means which is adapted to couple to and decouple from respective weights in the stack of weights. The lift cable, which is thereby coupled to the selector rod by the selector pin, is adapted to permit a user of the weight lifting machine to pull the lift cable or move a lift bar and thereby raise the weights coupled to the selector rod from their respective rest positions to their respective elevated positions.

[0009] In other forms, the lift cable, or lift bar, is coupled to a handle, which the user can grasp to move a selected weight or weights from the rest position to the elevated position. The machine preferably includes a frame, which supports the lift cable, or lift bar, and the guide. For example, the lift cable may be supported on the frame by at least one pulley. Furthermore, the frame may include a seat on which the user may sit when using the machine.

[0010] As will be understood from the foregoing, the weight lifting machine of the present invention provides for ease of changes in resistance.

[0011] These and other objects, advantages, purposes and features of the invention will become more apparent from the study of the following description taken in conjunction of the drawings.

DESCRIPTION OF THE DRAWINGS

[0012]FIG. 1 is a front elevation of a weight lifting machine incorporating the present invention;

[0013]FIG. 2 is a side elevation of the weight lifting machine of FIG. 1;

[0014]FIG. 3 is a side view of the selection pin with the magnet housing and grip mounted thereto.

[0015]FIG. 4 is a front view of the magnet.

[0016]FIG. 5 is a side view of the magnet.

[0017]FIG. 6 is a side view of the rod having cavities to receive the selection pin.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Referring to FIG. 1, a weight lifting or exercise machine 10 is shown which includes a frame 12 that supports a pair of generally vertically oriented guide rods or rails 14 and 16 on which a stack of weights 18 and a carriage 22 are moveably mounted. As will be described in more detail below, the individual weights 20 of stack 18 are selectively coupled and decoupled from carriage 22 to increase or decrease the resistance for the user of machine 10.

[0019] Carriage 22 comprises a base member 23 which may include a pair of spaced apart bushings or bearings 23 a and 23 b, for example linear bearings. Bushings 23 a and 23 b define transverse passages through base 23 and guide carriage 22 on guide rods 14 and 16. Mounted to base 23 of carriage 22 is a lift member or lift cable 24. Lift cable 24 is secured at one end 24 a to carriage 22 by a coupler 24 b, including for example a threaded coupler, and secured to a handle 25 at a second end 24 b. Lift cable 24 extends from carriage 22 upwardly through frame 12 and over a pair of spaced apart cable pulleys 26 and 28 which position handle 25 over a workout bench or seat 30. In this manner when handle 25 is pulled downwardly, carriage 22 and any weights 20 which are coupled to carriage 22 move up guide rods 14 and 16, with the resistance on the handle being a function of the number of weights coupled to the carriage 22.

[0020] Referring to FIGS. 1 and 2, frame structure 12 includes a pair of horizontally spaced front and back base members 34 and 36 which are interconnected by opposed side base members 38 and 40. Frame structure 12 further includes front and back upper members 42 and 44 which are similarly interconnected by opposed side upper members 46 and 48 and which are further interconnected to base members 32, 34, 36, and 38 by a plurality of column members 50, 52, 54, and 56, which form a rigid frame and support guide rods 14 and 16. Guide rods 14 and 16 are mounted to upper members 46 and 48 by a transverse cross member 58 which extends between upper members 46 and 48 on one end and are similarly mounted to base members 38 and 40 by a lower transverse member 60 which extends between lower base members 38 and 40. Pulleys 26 and 28 are respectfully rotatably supported on frame 12 by a cantilever support member 62 which is mounted to upper members 42 and 44. Pulleys 26 and 28 are rotatably mounted on member 62 by pins 26 a and 28 a, respectively, which extend through transverse holes 62 a provided in member 62. It can be appreciated, in this manner at least the location of pulley 26 can be adjusted to accommodate different weight lifting configurations.

[0021] As best seen in FIGS. 1 and 2, seat 30 is positioned forwardly of frame 12 and is supported from a vertical intermediate frame member 64 which is secured to front base member 34. Seat 30 is preferably supported from vertical member 64 by a braced cantilever member 66. In addition to seat 30, exercise machine 10 may include a leg restraint 33. Leg restraint 33 is positioned forward of seat 30 so that the user can restrain himself or herself from lifting off seat 30 when working out with a weight that exceeds his or her own body weight. Restraint 33 includes a pair of cylindrical padded members 33 a and 33 b which are rotatably mounted on a tubular member 35 which is similarly mounted to vertical support or member 64 by a cantilever member 68. Preferably, both seat 30 and restraint 33 are adjustably mounted to vertical support 64 to accommodate users of different height and proportions. In this manner, when a user is seated on seat 30, the user may position his or her legs under restraint 33 and pull on handle 25 which in turn pulls on carriage 22 by way of lift cable 24. As described previously, the amount of resistance depends on the number of individual weights 20 that are coupled to carriage 22. As seen in FIG. 6, carriage 22 includes downwardly depending selection rod or member 65. In preferred form, selection rod 65 includes a plurality of cavities 71, which can be milled, cast or formed from welded components forming selection rod 65. Referring to FIGS. 1 and 2, selection rod 65 extends through central openings provided in weights 20 and includes respective cavity 71 for each individual weight 20 in stack 18 so that each weight can be individually and selectively coupled to selection rod 65.

[0022] In order to reduce the impact on frame 12 when weights 20 are lowered to their respective starting positions, rails 14 and 16 preferably include springs 120 interposed between the lowermost weight 20′ and transverse member 60.

[0023] As seen in FIG. 3 selector pin 300 includes shaft 301 and grip or pull means 302. Magnetic means 303 is shown in the preferred position adjacent to grip 302 and substantially surrounding shaft 301. Optional magnet housing 304 protects the magnet from damage due to repeated contact with the weights, dropping, misuse, and the like. Preferably housing 304 is a plastic or polymer material. Magnetic means 303 may be alternatively positioned at any distance along shaft 301 as long as it is near enough to a weight 20 to become magnetically attracted thereto sufficiently to retain selector pin 300 in place when inserted through, above or below a weight 20 and into a cavity 71 of rod 65, thereby selectively coupling weight 20 to rod 65. Advantageously, at least a portion of magnet 303 is niobium.

[0024] Grip 302 may be attached in known ways such as with pin 301 being threaded and threadable into grip 302, pin 301 being pinned, glued, pressed, crimped, or the like to grip 302, or pin 301 and grip 302 molded or cast as a single unit or the like. Grip 302 may be applied to hold magnet 303 in place, to encase magnet 303, or cast or molded at least partly around magnet 303 in order to retain it in place. Magnet 303 may be exposed, partly encased, or completely encased.

[0025] The present inventive magnetically anchored, quick release pin is usable in any ferrous-related application which currently employs or is capable of employing a quick release or releasable pin. Known releasable pins are of the plunger-button style or the ball detent style, both of which have performance and reliability deficiencies which are overcome by the present inventive magnetically anchored quick release pin.

[0026] Furthermore, while various forms of the invention have been shown and described, other forms are being apparent to those skill in the art. It should be understood that the general concept of a stack a weights with a selection member with magnetic rod or pin means can also be used in other weight lifting configurations. Therefore, the embodiment of the invention shown in the drawings is not intended to limit the scope of the invention. 

In the claims:
 1. A releasable article comprising: a rod shaped for insertion through a first member and into an opening in a second member such that said rod magnetically attaches to the exposed side of the first member and substantially prevents movement between said first member and said second member.
 2. The releasable article of claim 1 wherein at least one of said first member and said second member contains iron or a ferrous component.
 3. The releasable article according to claim 1 wherein the rod has a grip attached thereto.
 4. The releasable article according to claim 3 wherein said grip is attached to the rod by being pinned to, glued to, pressed to, or crimped to the grip.
 5. The releasable article according to claim 3 wherein said rod and grip are molded or cast as a single unit.
 6. The releasable article according to claim 3 wherein the grip retains the magnetic means by pressure against a shoulder of the rod, by encasing the magnetic means, or by being cast or molded at least partially encasing the magnetic means.
 7. The releasable article accordingly to claim 6 wherein the magnetic means is positioned between the grip and the rod with the magnetic means being completely exposed, partially encased, or completely encased.
 8. A weight lifting machine comprising: a stack of weights, each of said weights having an opening, said openings being aligned to define a passage through said stack of weights; at least one guide, each of said weights being slidably mounted on said at least one guide and being movable along said guide from a rest position to an elevated position; a selector member, said selector member having a downwardly depending member, said downwardly depending member having a passage therethrough, said selector member including a rod or pin having magnetic means, said rod or pin shaped for insertion through a weight in the stack of weights and into the passage of the downwardly depending member such that said magnetic means attaches to the exposed side of a respective weight in said stack of weights; and a lift means coupled to said selector member, said lift means being adapted to permit a user of said weight lifting machine to raise said weights attached to said selector member from its respective rest position to its respective elevated position.
 9. A weight lifting machine according to claim 8, wherein said lift means is coupled to a handle, ankle pad assembly, or a shoulder pad.
 10. A weight lifting machine according to claim 9, further comprising a frame, said lift means being supported by said frame.
 11. A weight lifting machine according to claim 10, wherein said lift means includes a lift cable supported on said frame by at least one pulley.
 12. A weight lifting machine according to claim 11, further comprising a seat positioned below said handle, said seat being supported by said frame.
 13. A weight lifting machine according to claim 7, wherein said selector member further includes a carriage, said downwardly depending member extending downwardly from said carriage, and said at least one guide extending through said carriage.
 14. A weight lifting machine comprising: a frame; a stack of weights, each of said weights having an opening therein or between adjacent weights, said openings being aligned to define a passage through said stack of weights; a least one guide supported by said frame, said weights being slidably supported on said guide and being movable along said guide from a rest position to an elevated position; a selector member extending through said passage, said selector member having a plurality of cavities formed therein and a selector pin having a magnetic means, which pin is insertable through the selector member and weight stack whereby said magnetic attraction of said selector pin affixes said pin to a respective weight in said stack of weights; and a lift member supported by said frame, said lift member being coupled to said selector member and being adapted to permit a user of said weight lifting machine to raise said weights coupled to said selector member by said selector pin from said rest position to said elevated position.
 15. A weight lifting machine according to claim 14, wherein said lift member includes a lift cable.
 16. A weight lifting machine according to claim 15, wherein said lift cable is supported by a pair of pulleys attached to said frame.
 17. A weight lifting machine according to claim 14, wherein said at least one guide extends through said weights.
 18. A weight lifting machine according to claim 14, wherein said at least one guide includes springs, said springs being at least partially compressed when said weights are in their respective rest positions.
 19. A weight lifting machine according to claim 16, wherein said guide includes at least one guide rod.
 20. A weight selector assembly in combination with a plurality of aligned weight plates, comprising: a base member; and a selector rod mounted on said base member, wherein said selector rod includes a shaft extending through the weight plates and having a longitudinal axis, and a weight plate engagement member, wherein said engagement member has a magnetized portion whereby it may be affixed to said shaft at discrete axial locations, and said engagement member being extendable through or under a weight plate. 